Few minor changes:
All commands now accept variable called "Options". This can be used to collect
all options for which Perforce has not defined an environment variable -
for example the undocumented "-C1" for p4d to start a case insensitive server.

p4d also accepts the variables P4USER and P4PASSWD. These are only used for
stopping the service, which is done first via "p4 admin stop". Note that if
the stop via the admin command fails, p4dcfg will stop the service via a kill